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Main => Main Forum => Topic started by: Midcoastsurf on July 20, 2018, 03:06:37 pm

Title: Wells monitor on NFL Blitz - only V Sync? (no H Sync?)
Post by: Midcoastsurf on July 20, 2018, 03:06:37 pm

This monitor was never working right when I got this project.  I only see 5 wires coming into the connector (the purple one temporarily connected to pin 1 is coming off the V Sync on the JAMMA connector.

Should there be an H Sync wire plugged into this header pin?  I'm confused.  I also get mixed comments on which pin the sync wire should be on.  Some say pin 1 at the end, but the board shows V Sync next to the ground wire.

Someone wrote WG 25k7401 on the top of the chassis frame, so I assume that's what the monitor is.

Title: Re: Wells monitor on NFL Blitz - only V Sync? (no H Sync?)
Post by: Malenko on July 20, 2018, 03:31:50 pm

is the pcb in STD or MED res mode? Any other PCBs you can test with?

I had a blitz back in the day, it was wired the way yours is.

Title: Re: Wells monitor on NFL Blitz - only V Sync? (no H Sync?)
Post by: Midcoastsurf on July 20, 2018, 04:01:44 pm

Quote from: Malenko on July 20, 2018, 03:31:50 pm

is the pcb in STD or MED res mode? Any other PCBs you can test with?

I had a blitz back in the day, it was wired the way yours is.

I only have a GT '02 board (no hard drive)...but I guess the boot screen would come up, right?

I also just read that the two sync inputs should be both tied into the single V Sync wire coming off the JAMMA connector.  Which is interesting, because someone originally had two wires connected to the single white-yellow wire going into the JAMMA connector (but now only one pin on the end).  I'm gonna try copying this set up...

Title: Re: Wells monitor on NFL Blitz - only V Sync? (no H Sync?)
Post by: big10p on July 23, 2018, 07:05:31 am

Have you tried just adjusting the H sync pot? All my JAMMA cabs just have the H sync pin connected which provides composite sync. The V sync wire is not connected.